[NHRC-user] NHRC-Micro Problems

[Roy]

I just bought a used NHRC-Micro from a guy on Ebay a few days ago. He still
has several of them for sale at $80 a piece. Money is tight so that's the
route I took as opposed to spending another 40 bucks to buy new. Might have
to buy another one from him if I can't fix this one. The controller was
working fine here at the house. I had just got it programmed and working
well as a temporary cross band repeater between UHF and VHF handhelds when
something happened last night. The RX audio voltage started going to ground
on the controller. Not sure what I did (I might have toasted something by
connecting a speaker to the RX audio high and low on the terminal strip
without thinking) but this is how I had it set up:

All connections were made on a terminal strip. I was using a second
controller in the configuration to use a +COS because the harness that came
with the Micro did not have a +COS lead in the connector but only a -COS
lead. So I provided the -COS source for the Micro with the extra relay on
the second controller. The +COS source for the second controller was about
3.5V unsquelched from the audio high lead from the handheld used as the RX.
The PTT from the handheld used as the TX had 5V and was connected to PTT on
the Micro and to the wiper on the relay. TX and RX audio was connected to
the Micro. Everything was fine with this setup for awhile. When the squelch
opened on RX the +COS saw 3.5V and keyed controller 2. The PTT on controller
2 went to ground and the N.C. lead on the relay opened and activated
the -COS for the Micro. The PTT on the Micro went to ground and keyed the
TXer. The courtesy tones and CW sounded good. It programmed very well with
the serial cable and your software. I don't know how the audio sounded thru
this setup as I had no way of TXing and hearing it at the same time. As of
today I do have a way but now the Micro has a problem with this RX audio
going to ground. When the squelch opens, the RX audio high from the RXer
quickly loses voltage going from 3.5V to almost 0 in about 3 seconds almost
like a quick discharge of a capacitor. When ground is removed from the Micro
the RX audio voltage remains steady at 3.5V when unsquelched. So sounds like
one of those microscopic components went south on me.

I would really appreciate any clues on this. We are planning a trip to the
area of my repeater about 200 miles away for next weekend and I really need
a controller to take with me to install. These components are very small on
the Micro so looks like a repair job (by me) is not an option. Looks like I
may be out 80 bucks and a postponement of the much needed controller
install. I will hold out some hope that maybe someone on this list might be 
able to help me.

Thanks for your time.

Roy
N7DWC